They are essential to combat the climatic emergency, harbor biodiversity, can reduce fires and lower temperatures, improve air quality, promote good mental health … We talk about trees, lungs, and allies of nature, responsible for capturing carbon dioxide, host millions of species and participate essentially in the global food chain. In spite of this, we continue cutting them at a fast pace, endangering the existence of the planet and all its inhabitants.
New research throws a new potential on forest cover: trees should be used to replace air conditioning, according to this new study by the British Forest Commission, supported by the Department of Environment, Food, and Rural Affairs. Their results revealed that areas with a high tree density were up to 4 degrees colder than places in the same city without vegetation.
By following published guidelines and advice, including the selection of trees that are better for cooling and planting near offices, researchers found that air conditioning could be reduced in cities by up to 13 percent, saving £ 22 million per year and reducing the carbon footprint of urban environments.
The study authors noted the hot summer of 2018 and argued that city residents could have more comfort during heat waves if more trees are planted in towns and cities.
The Meteorological Office recently predicted that the United Kingdom could experience four heat waves of more than 30 degrees per year in 2050.
Which trees are most appropriate to replace air conditioning?
The scientists found that larger trees with a greater amount of leaf area, dense crowns and high rates of perspiration are the best for local cooling.
The research, which was conducted by the University of Reading, discovered that some of the best trees for local cooling in London were the London Plane Tree, the Sessile Oak, and the Cherry Tree. Also, they should be planted in areas where people can walk or sit in the shade. It is also recommended to plant additional foliage in a way that protects houses and buildings from the sun.
Trees help areas to cool by a process called evapotranspiration, which causes water produced during respiration to evaporate from tree leaves, cooling the air.
“In collaboration with Ricardo Energy & Environment and the University of Uppsala in Sweden we have identified which characteristics of the trees are linked to the greater cooling and we have proposed a methodology that can be used by urban planners and tree managers to compare and select tree species according to its cooling capacity ”, revealed from The Forestry Commission.
Selected trees should also be drought-tolerant, as they will be planted in warm and dry areas in inland cities.
The Edinburgh Forestry Commission contributed to the investigation and found that between 2011 and 2014, air temperatures around Kensington Gardens were measured by finding a cooling of up to 4 ° C compared to nearby streets with less vegetation.